Cinética de redução do catalisador CuO/ZnO/Al2O3

Abstract

Recebido em 26/7/06; aceito em 18/5/07; publicado na web em 16/10/07 REDUCTION KINETICS OF A CuO/ZnO/Al 2 O 3 CATALYST. The reduction kinetics of a CuO/ZnO/Al 2 O 3 catalyst by hydrogen was investigated isothermally and by temperature programmed reduction (TPR). Two reducible Cu 2+ species were detected; the first one was identified as CuO bulk and the other as Cu 2+ strongly interacting with alumina, possibly in the form of copper aluminate. The activation energies for the reduction of these two species were 60 and 90 kJ mol-1 , respectively, and the reaction order with respect to hydrogen was one. The isothermal reduction data showed that the isotropic growth model is the most appropriate to describe the reaction rate data for both Cu 2+ species.